This invention relates to a mobile radio system, and more particularly, to a link connection procedure in a mobile radio system using an asynchronous transmission mode (ATM).
In general, a mobile radio system is known which comprises a plurality of radio base stations each of which is connected to a base station control apparatus by an asynchronous transmission mode (ATM) fashion.
In such a system, it is necessary for header information of 24 bits in an ATM cell to have an individual value in each of the radio base stations inasmuch as the header information must be recognized in the base station control apparatus on carrying out transmission and reception between the base station control apparatus and each of the radio base stations. The header information may be representative of an identifier and may be called a VPI/VCI in ATM fashion. When each of the radio base stations starts up in the mobile radio system, the VPI/VCI is not determined in each of the radio base stations. Therefore, it is necessary to individually allocate the VPI/VCI to each of the radio base stations by the base station control apparatus.
The base station control apparatus manages the VPI/VCI of each radio base station. The VPI/VCI at the time of setting to each radio base station may be different from the VPI/VCI at the subsequent time, by mistake such as a line error, as will be described later.
Inasmuch as the radio base station carries out reception of a message signal in accordance with the VPI/VCI, it is impossible for a specific one of the radio base stations to receive the message signal when the VPI/VCI varies in the specific radio base station. It is impossible to control the specific radio base station by the base station control apparatus. As a result, it is necessary for a person to go to the place where the specific radio base station is installed, in order to reset the specific radio base station.